DOCSLIB.ORG

The Official Magazine of The

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Official Magazine of The OceTHE OFFICIALa MAGAZINEnog OF THE OCEANOGRAPHYra SOCIETYphy CITATION Embley, R.W., Y. Tamura, S.G. Merle, T. Sato, O. Ishizuka, W.W. Chadwick Jr., D.A. Wiens, P. Shore, and R.J. Stern. 2014. Eruption of South Sarigan Seamount, Northern Mariana Islands: Insights into hazards from submarine volcanic eruptions. Oceanography 27(2):24–31, http://dx.doi.org/10.5670/oceanog.2014.37. DOI http://dx.doi.org/10.5670/oceanog.2014.37 COPYRIGHT This article has been published inOceanography , Volume 27, Number 2, a quarterly journal of The Oceanography Society. Copyright 2014 by The Oceanography Society. All rights reserved. USAGE Permission is granted to copy this article for use in teaching and research. Republication, systematic reproduction, or collective redistribution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The Oceanography Society. Send all correspondence to: [email protected] or The Oceanography Society, PO Box 1931, Rockville, MD 20849-1931, USA. DOWNLOADED FROM HTTP://WWW.TOS.ORG/OCEANOGRAPHY SPECIAL ISSUE ON UNDERSEA NATURAL HAZARDS Eruption of South Sarigan Seamount, Northern Mariana Islands Insights into Hazards from Submarine Volcanic Eruptions BY ROBERT W. EMBLEY, YOSHIHIKO TAMURA, SUSAN G. MERLE, TOMOKI SATO, OSAMU ISHIZUKA, WILLIAM W. CHADWICK JR., DOUGLAS A. WIENS, PATRICK SHORE, AND ROBERT J. STERN ABSTRACT. The eruption of South Sarigan Seamount in the southern Mariana arc activity. Seismic body waves and in May 2010 is a reminder of how little we know about the hazards associated with T-phases (waterborne acoustic waves) submarine explosive eruptions or how to predict these types of eruptions. Monitored produced by the eruptive events were by local seismometers and distant hydrophones, the eruption from ~ 200 m water recorded on seismometers on nearby depth produced a gas and ash plume that breached the sea surface and rose ~ 12 km islands (Searcy, 2013) and on submarine into the atmosphere. This is one of the first instances for which a wide range of pre- hydrophones and seismometers located and post-eruption observations allow characterization of such an event on a shallow 2,260 km to the east of South Sarigan submarine volcanic arc volcano. Comparison of bathymetric surveys before and after Seamount. The mid-Pacific instruments the eruptions of the South Sarigan Seamount reveals the eruption produced a 350 m near Wake Island are operated by the diameter crater, deeply breached on the west side, and a broad apron downslope with International Monitoring System (IMS) deposits > 50 m thick. The breached summit crater formed within a pre-eruption of the Comprehensive Nuclear Test dome-shaped summit composed of andesite lavas. Dives with the Japan Agency for Ban Treaty (CTBT) (Green et al., 2013). Marine-Earth Science and Technology Hyper-Dolphin remotely operated vehicle Precursory volcano-tectonic earthquakes sampled the wall of the crater and the downslope deposits, which consist of andesite began in early April 2010 and continued lava blocks lying on pumiceous gravel and sand. Chemical analyses show that the intermittently through April and early andesite pumice is probably juvenile material from the eruption. The unexpected May, with a significant increase in size eruption of this seamount, one of many poorly studied shallow seamounts of and number of swarms beginning on comparable size along the Mariana and other volcanic arcs, underscores our lack of May 11 (Searcy, 2013). Hydroacoustic understanding of submarine hazards associated with submarine volcanism. phases, interpreted as eruptive activity (Green et al., 2013; Searcy, 2013), began AN UNUSUAL ERUPTION an underwater eruption occurred on on May 27, reaching a peak during ON THE MARIANA ARC South Sarigan Seamount, a poorly a three-hour period early on May 29 An unexpected submarine volcanic surveyed submarine volcano lying with near-continuous volcanic tremor. eruption on the southern Mariana arc between Sarigan and Anatahan Islands Also during this time span, patches of (Figure 1a,b) in 2010 provides insights in the Commonwealth of the Northern discolored water were observed on the into the volcanic processes of submarine Mariana Islands (Figure 1a,b). The ocean surface (McGimsey et al., 2010) eruptions and the hazards these hidden eruption was unusual because this and infrasound events (atmospheric volcanoes pose. On May 28–29, 2010, seamount had no known historical acoustic signals) were recorded on a 24 Oceanography | Vol. 27, No. 2 143°E 144°E 145°E 144°E 145°E 146°E 143°E 144°E Dashed lines indicate145°E 142°E 144° 144°E146° 145°E 146°E 143°E 144°E 145°E M144°E 145°E 146°E a summit depths <500m a ar b ia Dashed lines indicate 142°E 144° M n 146° Dashed lines indicate 142°E 144° M 146°a Guguan summit depths <500m a M ar a a summit depths <500m a ar i T b b a Nikko summitComposite depths Cone <500m a riaa r b iann e Guguan naa n Guguan Guguan 22° a 143°E 144°E Composite 145°ECone 144°ET T c 145°E 146°E NikkoNikko BasalticComposite Cone Cone Tr re h Nikko re n 23°N 22° n 22° n c 22° c BackarcDashedBasalticBasaltic linesAxis Cone Cone indicate 142°E 144° M 146° chh 17°N Basaltic Cone a h Zealandia (s) 23°N 23°N summit depths <500m a 23°N a ri b a 17°N Backarc Axis 17°N Backarc Axis n 17°N MarianaBackarc Islands Axis a W Sarigan GuguanZealandiaZealandia (s) (s) M T Sarigan Nikko Composite Cone Maug r 20° e MarianaMariana Islands Islands a WW Sarigan Sarigan Mariana Islands MM n W Sarigan SariganSarigan Syoyo 22° c Sarigan Maug ri 20° Maug h South Basaltic Cone 20° 20° aaa 23°N SyoyoSyoyo Syoyo a ri South >5000 0 17°N DepthBackarc (m) Axis riri ZealandiaSouth (s)SouthSarigan n Anatahan a >5000>5000 DepthDepth (m) (m) 00 a a SariganSariganSeamount n a Anatahan n Anatahan Mariana Islands M n W SariganAnatahan Sarigan Seamount a Seamount Maug a Seamount a 20° Pagan A 18° a Syoyo Pagan Pagan A ri A 18° South Pagan r 18° A Fukujin 18° c a r Fukujin >5000 Depth (m) 0 r Sarigan b r 22°N Fukujin c c Fukujin n c Anatahan b c 22°N b Diamante (s) 22°N b Seamount 16°N a 22°N Diamante (s) Diamante (s) 16°N Diamante (s) 16°N S SariganPagan 16°N A 18° S Sarigan Fukujin r 16° c c 16° 16° b 22°N 16° Diamante (s) Kasuga-2Kasuga-2 RubyRuby 16°N Kasuga-2 EifukuEifuku Saipan Ruby Eifuku S SariganSaipan Saipan W Saipan DaikokuDaikoku 16° WW Saipan Saipan Kasuga-2 Daikoku W Saipan Ruby Eifuku Saipan Saipan 14°N 14°N h Saipan h Saipan 14°N c h Daikoku nc c EsmeraldaW Saipan Saipan 14°N Guam e n h Esmeralda Guam rre nc Km 100 T ren Esmeralda 21°N Guam 21°N Km 100 Tre Tinian Tinian 21°N 15°N Km14°N 100 T Saipan h 15°N Tinian 21°N c Esmeralda Tinian 15°N Guam en Farallon de 15°N Farallon deKm 100 Tr 21°N FarallonFarallonPajaros de de W TinianTinian Pajaros W Tinian 15°N PajarosFarallon de WW T Tinianinian Ahyi Makhahnas PajarosAhyi W Tinian Makhahnas AhyiAhyi W Rota Makhahnas Ahyi Makhahnas W Rota Supply Maug W Rota SupplyReef MaugMaug Rota Maug 20°N Supply 20°N Supply Rota 14°N Rota 14°N ReefReefReef Rota 20°N 20°N 20°N 14°N 14°N 14°N Asuncion TMTM proj.proj. CMCM 144°E144°E TM proj. CM 145°E Asuncion TM proj. CM 145°E TM proj. CM 144°E AsuncionAsuncionCheref Guam TM proj. CM 145°E TM00 proj. CMkm 144°E 100100 0 TM proj.km CM 145°E100 TM proj. CM 144°Ekm Cheref Guam TMkm proj. CM 145°E 0 km 100 CherefCheref GuamGuam 0 km 100 0 0 km km 100100 0 0 kmkm 100100 c 175 d c 175500 d 500 c c 175175 dd 1000500 1000500 1500 Depth (m) Depth (m) 15001000 Depth (m) 1000 200020001500 Depth (m) 1500 Depth (m) 500500 m m mid-imagemid-image2000 2000 P2P2 500 m P2 P2 P1P1 500 m P1P1 mid-image P1 P2 mid-image P2 P1 P2 P1 P2 N N N N e Difference Grids EM122 Bathymetry MV1302a f Difference Grids e MV1302a - TN153 (positive changes) N EM12225 m Bathymetry grid-cell size MV1302a Nf MV1302aMV1302a - TN153 - Combo (positive of TN153 changes) & EW0202 (negative changes)N N 25 m grid-cell size -1400 MV1302a - Combo of TN153 & EW0202 (negative changes) -1400 16°38'N e Difference Grids EM122 Bathymetry MV1302a 16°38'N f 16°38'N 16°38'N 16°38'N DifferenceMV1302a Grids - TN153 (positive changes)+100? EM122 Bathymetry MV1302a 16°38'N e +100? 25 m grid-cell size f MV1302aMV1302a - TN153 - Combo (positive of TN153 changes) & EW0202 (negative changes) -1000 25 m grid-cell size -1400 MV1302a - Combo of TN153 & EW0202 (negative-50 changes)-150 -1000 16°38'N -1400 16°38'N 16°37'N -50-50 -150-150 16°37'N 16°38'N +100? P1 -2000 P1 16°38'N 16°37'N 16°37'N 16°37'N 16°37'N +100?+50 -200 16°37'N P1 -2000-2000 P1 -1000 +50 -50 -200 -1000 +50 -150 -500 -300 -1000 16°36'N 16°36'N 16°37'N +50 to +100 -50 -1000-1000 16°37'N -150 -1500 -500 -300 Polygon constraint P1 -2000 P1 16°37'N 0 16°37'N 16°36'N 16°36'N Polygon constraint 16°36'N +50+50 toto +100+100 for positive volumes -200 16°36'N +50 for negative volumes -1500-1500 -200 Depth P1 -2000 P1 00 Changes Polygon constraint Polygon constraint-200 +50 -1000 forfor positivepositive volumesvolumes -200 16°35'N -500 Depth-100 to - 200 forfor negativenegativeP2 volumesvolumes P2 -300 16°35'N 16°36'N +50 toChanges +100 -1000 16°36'N 0 Km 2 -500 0 Km 2 -1500 -800 -300 16°35'N 16°35'N 16°35'N -100-100Geographic toto -- 200200 proj.
Load more

Recommended publications
  • Geology, Geochemistry and Earthquake History of Loieihi Seamount, Hawaiei's Youngest Volcano
    ARTICLE IN PRESS Chemie der Erde ] (]]]]) ]]]–]]] www.elsevier.de/chemer INVITED REVIEW Geology, geochemistry and earthquake history of Lo¯"ihi Seamount, Hawai"i’s youngest volcano Michael O. Garciaa,Ã, Jackie Caplan-Auerbachb, Eric H. De Carloc, M.D. Kurzd, N. Beckera aDepartment of Geology and Geophysics, University of Hawai"i, Honolulu, HI 96822, USA bAlaska Volcano Observatory, U.S.G.S., Alaska Science Center, Anchorage, AK 99508, USA cDepartment of Oceanography, University of Hawai"i, Honolulu, HI 96822, USA dDepartment of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA Received 6 June 2005; accepted 20 September 2005 Abstract A half-century of investigations are summarized here on the youngest Hawaiian volcano, Lo¯"ihi Seamount. It was discovered in 1952 following an earthquake swarm. Surveying in 1954 determined it has an elongate shape, which is the meaning of its Hawaiian name. Lo¯"ihi was mostly forgotten until two earthquake swarms in the 1970s led to a dredging expedition in 1978, which recovered young lavas. The recovery of young lavas motivated numerous expeditions to investigate the geology, geophysics, and geochemistry of this active volcano. Geophysical monitoring, including a real- time submarine observatory that continuously monitored Lo¯"ihi’s seismic activity for 3 months, captured some of the volcano’s earthquake swarms. The 1996 swarm, the largest recorded in Hawai"i, was preceded earlier in the year by at least one eruption and accompanied by the formation of a 300-m deep pit crater, Pele’s Pit. Seismic and petrologic data indicate that magma was stored in a 8–9 km deep reservoir prior to the 1996 eruption.
    [Show full text]
  • Coastal and Marine Ecological Classification Standard (2012)
    FGDC-STD-018-2012 Coastal and Marine Ecological Classification Standard Marine and Coastal Spatial Data Subcommittee Federal Geographic Data Committee June, 2012 Federal Geographic Data Committee FGDC-STD-018-2012 Coastal and Marine Ecological Classification Standard, June 2012 ______________________________________________________________________________________ CONTENTS PAGE 1. Introduction ..................................................................................................................... 1 1.1 Objectives ................................................................................................................ 1 1.2 Need ......................................................................................................................... 2 1.3 Scope ........................................................................................................................ 2 1.4 Application ............................................................................................................... 3 1.5 Relationship to Previous FGDC Standards .............................................................. 4 1.6 Development Procedures ......................................................................................... 5 1.7 Guiding Principles ................................................................................................... 7 1.7.1 Build a Scientifically Sound Ecological Classification .................................... 7 1.7.2 Meet the Needs of a Wide Range of Users ......................................................
    [Show full text]
  • Articles Ranging in Resents Both Gravitational Acceleration and the Effect of Bed Size from Tens of Meters to a Few Centimeters in Diameter
    Nat. Hazards Earth Syst. Sci., 6, 671–685, 2006 www.nat-hazards-earth-syst-sci.net/6/671/2006/ Natural Hazards © Author(s) 2006. This work is licensed and Earth under a Creative Commons License. System Sciences Numerical simulation of tsunami generation by cold volcanic mass flows at Augustine Volcano, Alaska C. F. Waythomas1, P. Watts2, and J. S. Walder3 1U.S. Geological Survey, Alaska Volcano Observatory, Anchorage, AK, USA 2Applied Fluids Engineering Inc., Long Beach, CA, USA 3U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, WA, USA Received: 18 April 2006 – Revised: 22 June 2006 – Accepted: 22 June 2006 – Published: 26 July 2006 Abstract. Many of the world’s active volcanoes are situated 1 Introduction on or near coastlines. During eruptions, diverse geophysical mass flows, including pyroclastic flows, debris avalanches, Many of the world’s active volcanoes are located within a and lahars, can deliver large volumes of unconsolidated de- few tens of kilometers of the sea or other large bodies of wa- bris to the ocean in a short period of time and thereby gen- ter. During eruptions, large volumes of volcaniclastic debris erate tsunamis. Deposits of both hot and cold volcanic mass may enter nearby water bodies, and under certain conditions, flows produced by eruptions of Aleutian arc volcanoes are this process may initiate tsunamis (Tinti et al., 1999; Tinti exposed at many locations along the coastlines of the Bering et al., 2003). Worldwide, tsunamis caused by volcanic erup- Sea, North Pacific Ocean, and Cook Inlet, indicating that tions are somewhat infrequent (Latter, 1981); however, doc- the flows entered the sea and in some cases may have ini- umented historical cases illustrate that loss of life and prop- tiated tsunamis.
    [Show full text]
  • Plumbing System Dynamics at Kolumbo Submarine Volcano, Greece, Prior to the 1650 CE Explosive Eruption
    Goldschmidt2019 Abstract Plumbing system dynamics at Kolumbo submarine volcano, Greece, prior to the 1650 CE explosive eruption F. MASTROIANNI1,2,*, I. FANTOZZI2, C.M. PETRONE3, G.E. VOUGIOUKALAKIS4, E. BRASCHI5, L. FRANCALANCI2 1DST, University of Pisa, Via S. Maria 53, Pisa, IT (*correspondence: [email protected]) 2DST, University of Florence, Via G. LaPira, 4, Florence, IT 3The Natural History Museum, CromWell Road, London, UK 4HSGME, S. Lui 1, Olympic Village, Athens, GR 5CNR-IGG, Via G. LaPira, 4, Florence, IT Kolumbo is the largest of tWenty submarine volcanic cones tectonically aligned in the transtentional Anydros basin, NE of Santorini, representing one of the most seismically active Zones in the South Aegean Volcanic Arc. Kolumbo explosively erupted in 1650 CE, causing the death of 70 people on Santorini. Explorative cruises employing ROVs shoWed the presence of a high temperature (220°C) hydrothermal field With CO2-rich discharges and accumulation of acidic Water at the bottom of the crater (505m bsl) [1], increasing the haZard of this active system. A possible magma chamber Was recognized beloW the crater at depth 9-6 km by seismic data [2], Which is separated from the storage system of Santorini, as suggested also for the mantle source by geochemical data [3]. We present neW petrographic, geochemical and isotopic data (on Whole-rock, minerals and glasses) of samples collected during the cruises. Most samples represent the juvenile products of the 1650 CE activity, characterizing the different magmas interacting before the eruption. They consist of White rhyolitic pumices With grey and black bands, also including centimetric to millimetric, basaltic-andesitic enclaves.
    [Show full text]
  • Explosive Subaqueous Eruptions: the Influence of Volcanic Jets on Eruption Dynamics and Tephra Dispersal in Underwater Eruptions
    EXPLOSIVE SUBAQUEOUS ERUPTIONS: THE INFLUENCE OF VOLCANIC JETS ON ERUPTION DYNAMICS AND TEPHRA DISPERSAL IN UNDERWATER ERUPTIONS by RYAN CAIN CAHALAN A DISSERTATION Presented to the Department of Earth ScIences and the Graduate School of the UniversIty of Oregon In partIaL fulfiLLment of the requirements for the degree of Doctor of PhiLosophy December 2020 DISSERTATION APPROVAL PAGE Student: Ryan CaIn CahaLan Title: ExplosIve Subaqueous EruptIons: The Influence of Volcanic Jets on EruptIon DynamIcs and Tephra DIspersaL In Underwater EruptIons This dissertatIon has been accepted and approved in partIaL fulfiLLment of the requirements for the Doctor of PhiLosophy degree in the Department of Earth ScIences by: Dr. Josef Dufek ChaIrperson Dr. Thomas GIachettI Core Member Dr. Paul WaLLace Core Member Dr. KeLLy Sutherland InstItutIonaL RepresentatIve and Kate Mondloch Interim VIce Provost and Dean of the Graduate School OriginaL approvaL sIgnatures are on fiLe wIth the UniversIty of Oregon Graduate School. Degree awarded December 2020 II © 2020 Ryan Cain Cahalan III DISSERTATION ABSTRACT Ryan CaIn CahaLan Doctor of PhiLosophy Department of Earth ScIences December 2020 Title: ExplosIve Subaqueous EruptIons: The Influence of Volcanic Jets on EruptIon DynamIcs and Tephra DIspersaL In Underwater EruptIons Subaqueous eruptIons are often overlooked in hazard consIderatIons though they represent sIgnificant hazards to shipping, coastLInes, and in some cases, aIrcraft. In explosIve subaqueous eruptIons, volcanic jets transport fragmented tephra and exsolved gases from the conduit into the water column. Upon eruptIon the volcanic jet mIxes wIth seawater and rapidly cools. This mIxing and assocIated heat transfer ultImateLy determInes whether steam present in the jet wILL completeLy condense or rise to breach the sea surface and become a subaeriaL hazard.
    [Show full text]
  • A Different Ocean Acidification Hazard—The Kolumbo Submarine Volcano
    A different ocean acidifi cation hazard—The Kolumbo submarine volcano example Peter G. Brewer Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, California 95039, USA Detailed knowledge of the geochemistry of CO2, the signature mol- column with its large capacity for dissolution. If transport overcomes this ecule of the 21st century, is a modern day requirement for almost all geo- aqueous chemical sink—the bubble streams typically dissolve within ~10 chemists. Concerns over CO2 driven contemporary climate change, its m rise—the gas will be exposed to the atmosphere at the wind-swept open relationship to past climates in Earth history, skills required for geologic ocean surface. CO2 sequestration, and the rapid emergence of ocean acidifi cation as an There is also the matter of scale. The estimated 400 metric tons environmental threat are all prime subject matter for the literate geoscien- of dissolved CO2 in the Kolumbo crater is far less than the 100,000 – tist today. In this issue of Geology, Carey et al. (2013, p. 1035) describe 300,000 tons believed to have been released in the Lake Nyos event. Of a new, interesting, and quite powerful natural example of the intersection course, we could be at an early stage of the CO2 buildup, and over time, of these concerns in describing the build-up of a large body of acidic, far larger quantities could accumulate. Carey et al. show that the local dense CO2 rich sea water in the shallow crater of the Kolumbo volcano source is an extensive hydrothermal vent fi eld, releasing almost pure close to the Mediterranean island of Santorini.
    [Show full text]
  • Exploring Submarine Arc Volcanoes Steven Carey University of Rhode Island, [email protected]
    University of Rhode Island DigitalCommons@URI Graduate School of Oceanography Faculty Graduate School of Oceanography Publications 2007 Exploring Submarine Arc Volcanoes Steven Carey University of Rhode Island, [email protected] Haraldur Sigurdsson University of Rhode Island Follow this and additional works at: https://digitalcommons.uri.edu/gsofacpubs Terms of Use All rights reserved under copyright. Citation/Publisher Attribution Carey, S., and H. Sigurdsson. 2007. Exploring submarine arc volcanoes. Oceanography 20(4):80–89, https://doi.org/10.5670/ oceanog.2007.08. Available at: https://doi.org/10.5670/oceanog.2007.08 This Article is brought to you for free and open access by the Graduate School of Oceanography at DigitalCommons@URI. It has been accepted for inclusion in Graduate School of Oceanography Faculty Publications by an authorized administrator of DigitalCommons@URI. For more information, please contact [email protected]. This article has This been published in or collective redistirbution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The approval portionthe ofwith any permitted articleonly photocopy by is of machine, reposting, this means or collective or other redistirbution SP ec I A L Iss U E On Ocean E X P L O R ATIO N Oceanography , Volume 20, Number 4, a quarterly journal of The 20, Number 4, a quarterly , Volume O ceanography Society. Copyright 2007 by The 2007 by Copyright Society. ceanography Exploring O ceanography Society. All rights All reserved. Society. ceanography O Submarine Arc Volcanoes or Th e [email protected] Send Society. ceanography to: correspondence all B Y S T even C A R E Y an D H A R A LDUR SIGURD ss O N Three quarters of Earth’s volcanic activ- although a significant part of arc volca- tion of tsunamis (Latter, 1981).
    [Show full text]
  • Active Continental Margin
    Encyclopedia of Marine Geosciences DOI 10.1007/978-94-007-6644-0_102-2 # Springer Science+Business Media Dordrecht 2014 Active Continental Margin Serge Lallemand* Géosciences Montpellier, University of Montpellier, Montpellier, France Synonyms Convergent boundary; Convergent margin; Destructive margin; Ocean-continent subduction; Oceanic subduction zone; Subduction zone Definition An active continental margin refers to the submerged edge of a continent overriding an oceanic lithosphere at a convergent plate boundary by opposition with a passive continental margin which is the remaining scar at the edge of a continent following continental break-up. The term “active” stresses the importance of the tectonic activity (seismicity, volcanism, mountain building) associated with plate convergence along that boundary. Today, people typically refer to a “subduction zone” rather than an “active margin.” Generalities Active continental margins, i.e., when an oceanic plate subducts beneath a continent, represent about two-thirds of the modern convergent margins. Their cumulated length has been estimated to 45,000 km (Lallemand et al., 2005). Most of them are located in the circum-Pacific (Japan, Kurils, Aleutians, and North, Middle, and South America), Southeast Asia (Ryukyus, Philippines, New Guinea), Indian Ocean (Java, Sumatra, Andaman, Makran), Mediterranean region (Aegea, Cala- bria), or Antilles. They are generally “active” over tens (Tonga, Mariana) or hundreds (Japan, South America) of millions of years. This longevity has consequences on their internal structure, especially in terms of continental growth by tectonic accretion of oceanic terranes, or by arc magmatism, but also sometimes in terms of continental consumption by tectonic erosion. Morphology A continental margin generally extends from the coast down to the abyssal plain (see Fig.
    [Show full text]
  • Sharon R. Allen Is a Physical Volcanologist Who Has Worked On
    Sharon R. Allen is a physical volcanologist who Timothy H. Druitt is a volcanologist who works has worked on the processes and products of felsic on the processes and products of explosive volca­ effusive and explosive volcanism in both subaerial nism. His approaches include the field study of and submarine environments from a range of tec­ volcanic products, laboratory analogue experi­ tonic settings. She has been researching the South ments, and the petrology and chemistry of magmas. Aegean volcanic arc since 1993, first as a PhD He has used Santorini Volcano (Greece) as a natural student at Monash University (Australia), later as a laboratory for identifying fundamental questions post­doc at the University of Tasmania (UTAS) (Australia), and currently related to volcanism and for testing hypotheses. He obtained his PhD as a university associate at UTAS. Her scientific interests include subae­ at the University of Cambridge (UK) and is currently Professor of rial caldera forming eruptions, the dynamics of pyroclastic currents Volcanology at Clermont­Auvergne University (France). He was Editor­ on land and when interacting with water, submarine pyroclastic erup­ in­Chief of the Bulletin of Volcanology for four years and received the tions and mechanisms for the formation of pumice in submarine set­ 2018 Norman L. Bowen Award of the American Geophysical Union. tings. Her approach includes field studies of volcanic products and laboratory analogue experimentation. Lorella Francalanci is a geochemist and volcano­ logist who investigates active volcanoes to reveal Olivier Bachmann is a professor of volcanology the pre­eruptive processes that are relevant to the and magmatic petrology at the Eidgenössische dynamics of volcanic eruptions.
    [Show full text]
  • Basaltic Lava Domes, Lava Lakes, and Volcanic Segmentation on the Southern East Pacific Rise Scott M
    University of South Carolina Scholar Commons Faculty Publications Earth, Ocean and Environment, School of the 10-10-2000 Basaltic Lava Domes, Lava Lakes, and Volcanic Segmentation on the Southern East Pacific Rise Scott M. White University of South Carolina - Columbia, [email protected] Ken C. Macdonald University of California - Santa Barbara Rachel M. Haymon University of California - Santa Barbara Follow this and additional works at: https://scholarcommons.sc.edu/geol_facpub Part of the Earth Sciences Commons Publication Info Published in Journal of Geophysical Research, Volume 105, Issue B10, 2000, pages 23519-23536. White, S. M., Macdonald, K. C., & Haymon, R. M. (2000). Basaltic lava domes, lava lakes, and volcanic segmentationon the southern East Pacific Rise. Journal of Geophysical Research, 105 (B10), 23519-23536. © Journal of Geophysical Research 2000, American Geophysical Union This Article is brought to you by the Earth, Ocean and Environment, School of the at Scholar Commons. It has been accepted for inclusion in Faculty Publications by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 105,NO. B10, PAGES 23,519-23,536,OCTOBER 10, 2000 Basaltic lava domes, lava lakes, and volcanic segmentation on the southern East Pacific Rise ScottM. White, Ken C. Macdonald,and RachelM. Haymon Departmentof GeologicalSciences and Marine ScienceInstitute, University of California, SantaBarbara Abstract. Meter-scaleDSL-120 sonarmapping and coregisteredArgo
    [Show full text]
  • October 2018 Journal of the Institution of Environmental Sciences CONTENTS > How and Why Are the Oceans Changing?
    October 2018 Journal of the Institution of Environmental Sciences CONTENTS > How and why are the oceans changing? he number of people living on Earth will grow to due to the scales of change and variability, and the FEATURE 14 nine billion by 2050, with the population rising commitment, infrastructure and investment demanded in Exploring submarine volcanoes EDITORIAL fastest in low-lying coastal plains and cities. Driven the marine realm. Added to this, integrated cross-sectoral Ken Rubin describes our changing view of the seabed and its inhabitants, as we discover T more about underwater volcanoes. by growing public and political awareness, attention is approaches in businesses and governments can bring turning urgently to the ocean and coastal regions to about changes through influence and participative provide security for people and economic infrastructure processes, as much as by legislation and by an integrated against the sea’s dangers, including maritime accidents, vision of the land–sea interface. Finally, there is a need FEATURE 27 extreme weather, flooding and submarine geohazards. for appropriate, smart financial and policy instruments The cetaceans of the British Isles and a changing marine environment At the same time, there is a focus on the sea’s ability to de-risk investment in sustainable activities and recover Chiara Giulia Bertulli and Peter Evans describe ongoing shifts in abundance and to provide food, clean energy and minerals, whilst the economic potential of industries eroded by past distribution. protecting and
    [Show full text]
  • Archean Subduction Or Not? Evidence from Volcanic Geochemistry
    Archean Subduction or Not? Evidence from Volcanic Geochemistry Julian Pearce (Cardiff, UK) including collaboration with Hugh Smithies and David Peate Plan Part 1: Theory: Fingerprinting Subduction Volcanism Part 2: Life Cycles of Volcanic Arcs Part 3: Identification of Subduction Volcanism in the Palaeoproterozoic Part 4: Identification of Subduction Volcanism in the Middle to Late Archean Part 5: Identification of Subduction Volcanism in the Early Archean Plan Part 1: Theory: Fingerprinting Subduction Volcanism Part 2: Life Cycles of Volcanic Arcs Part 3: Identification of Subduction Volcanism in the Palaeoproterozoic Part 4: Identification of Subduction Volcanism in the Middle to Late Archean Part 5: Identification of Subduction Volcanism in the Early Archean Arc-aeology: Fingerprinting Arc Lavas in the Geological Record 1. Selective element mantle depletion by episodic enrichment In the mantle melt extraction towards arc front wedge. volcanic back-arc rear-arc intraplate arc ridge seamount volcano 2. Distinctive mantle flow pattern constrained by the F lithosphere B’ A’ subducting slab. C LT a sthenosphere HT B 3. Effects of high water UHT content on melting of the mantle wedge A 3. Effects of high water content in magmas on crystallization history and vesicularity/explosivity Arc-aeology: Fingerprinting Arc Lavas in the Geological Record 1. Selective element mantle depletion by episodic enrichment In the mantle melt extraction towards arc front wedge. volcanic back-arc rear-arc intraplate arc ridge seamount volcano 2. Distinctive mantle flow pattern constrained by the F lithosphere B’ A’ subducting slab. C LT a sthenosphere HT B 3. Effects of high water UHT content on melting of the mantle wedge A 3.
    [Show full text]